分娩相关基因在早产和足月产子宫肌层的差异表达及其意义

Differential expressions and clinical significance of labour-associated genes in preterm labour and term labour myometrium

目的研究分娩相关基因白介素-8(IL-8)、缩宫素受体(oxytocin receptor,OTR)和前列腺素H合成酶-2(prostaglandin H synthase type-2,PGHS-2)在早产和足月产子宫肌层的差异表达。方法选取17例早产临产(preterm labour,PTL)和31例早产未临产(preterm no labour,PTNL)孕妇作为研究组,6例足月临产(term labour,TL)和6例足月未临产(termno labour,TNL)孕妇作为对照组,活检取子宫(下段)肌层组织,采用实时荧光定量PCR(qRT-PCR)及Westernblot法检测各组子宫肌层中IL-8、OTR和PGHS-2mRNA及蛋白的表达水平,结合临床资料对检测结果进行统计学分析。结果子宫下段肌层中,IL-8mRNA的表达在PTL组显著低于TL组(P<0.01),但均显著高于对应的未临产组(PTNL,P<0.05;TNL,P<0.01);PGHS-2mRNA表达水平在PTL组显著低于TL组(P<0.05),而后者又显著高于TNL组(P<0.01);OTR mRNA和蛋白表达水平在各组中均未见显著差异(P>0.05);PGHS-2蛋白表达在TL组要显著高于TNL组(P<0.05)而在PTL与PTNL组间则未见明显区别(P>0.05)。Spearman非参数相关性分析显示在PTNL组中IL-8基因表达与孕周显著相关(r=0.294,P=0.042)。多元线性回归显示,早产组IL-8、OTR及PGHS-2基因表达均存在一定程度的相互影响,但在足月产组中则不明显。结论早产与足月产子宫肌层分娩相关基因表达存在显著的差异,可能与早产进程相关。

Objective To study the differential expressions of labour-associated genes,including interleukin-8 （IL-8）,oxytocin receptor （OTR） and prostaglandin H synthase type-2 （PGHS-2）） between preterm labour and term labour myometrium and their clinical significance.Methods Seventeen cases of preterm labour （PTL） and 31 cases of preterm no labour （PTNL） of pregnant women were selected as study group,while 6 cases of term labour （TL） and 6 cases term no labour （TNL） of pregnant women were chosen as control.Lower myometrial tissue biopsies were collected to detect the expressions of IL-8,OTR and PGHS-2 by real-time fluorescence quantitative polymerase chain reaction （qRT-PCR） as well as Western blot analysis.The expression data were then statistically analyzed in combination with clinical data.Results In the lower myometrial tissues,the mRNA levels of IL-8 and PGHS-2 were significantly lower in PTL group than in TL samples （P〈0.01 for IL-8 and P〈0.05 for PGHS-2）.IL-8 mRNA levels in PTL group and TL group were significantly up-regulated compared to those of PTNL and TNL groups respectively （P〈0.05 and P〈0.01 respectively）.There was no significant difference of PGHS-2 mRNA levels between PTL and PTNL groups （P〈0.05）,but the PGHS-2 mRNA level was significantly higher in TL group than in TNL group （P〈0.05）.The protein level of PGHS-2 was higher in TL group than in TNL group （P〈0.05）,but there was no difference of PGHS-2 protein among TL,PTL and PTNL groups （P〉0.05）.Correlation analysis suggested that the mRNA level of IL-8 was significantly correlated with gestational age in PTNL group （r=0.294,P=0.042）.Multiple linear regression analysis showed a mutual control effect of the expressions of IL-8,OTR and PGHS-2 in preterm but not in term labour group.Conclusion Our results show that there are significant differences of the expression of labour-associated genes in lower myometrum between preterm labour and term labour,which might becorrelated with the progression of preterm labour.